Sutures are used in a variety of surgical applications including closing ruptured or incised tissue, soft tissue attachment, anastomosis, attachment of grafts, etc. Conventionally, suturing of ruptured or incised tissues, for example, is accomplished by the surgeon passing the sharpened tip of a curved suturing needle with a suture attached to the opposite blunt end of the needle through the incised tissue segments to be sutured such that the needle tip penetrates the tissue segments causing the needle to span the incision. The needle is then pulled through the tissue segments manually causing the attached suture to follow the curved path of the needle. Usually a knot is tied at the trailing end of the suture to anchor the first stitch. This action is performed repetitively with application of tension to the needle to pull the entire suture through the tissue segments through subsequent stitches until the entire incised segments are sutured together with a plurality of stitches.
For example, conventional, open abdominal surgery, including OB-Gyn procedures such as Cesarean delivery, creates a substantial incision (typically eight or more inches in length) in the fascia. In major orthopedic surgery, such as total hip replacement, even longer incisions in two layers of fascia must be closed. The closure of fascia must be done carefully at the conclusion of the surgical procedure, prior to skin closure. Closing fascia by hand suturing is a routine, repetitive, and time-consuming procedure. Typical abdominal incisions may take as long as twenty minutes, while in the case of hip replacement surgery, fascia closure can take even longer. Alternative mechanical suturing devices, as well as staplers, bone anchors, and suture-based arterial closure devices have been used as alternatives to hand suturing in other applications, since manual suturing is a tedious and the speed of the procedure is mostly dependent on skill of the surgeon. Moreover, manual suturing involves the handling and manipulation of a sharp suturing needle with an instrument such as a needle forceps, which can result in slipping and inadvertent, accidental needle pricks through a surgeon's or nurse's gloves, posing a potential risk of infection for the surgeon, nurse, staff, and patient. Furthermore, the direct handling of the needle can cause the needle to become contaminated with pathogenic bacteria that can cause onset of infection at the site of the sutures. There is also a risk of the needle penetrating the bowel and causing a serious, and often fatal infection.
Suturing devices described in the art designed to overcome these limitations are, however, either unduly complex design and economically non-viable or relatively difficult to use and unsuited for precise manipulation for suturing areas that are not easily accessible. For example, the device disclosed in U.S. Pat. No. 4,557,265 has to be held sideways in relation to the direction of the incision being closed. Another limitation of prior art suturing devices is their inability to provide positive control over the needle and suture during the suturing process. This can result in non-uniform sutures with either overly loose or overly tight stitches, which can cause excessive bleeding and risk tearing the repaired tissue in the patient.
A suturing device that maintains a positive control over the suturing needle and is capable of providing uniform stitches is disclosed in U.S. Pat. Nos. 5,437,681 and 5,540,705. The disclosed device requires a “scissors-like” grip and is operated by the surgeon's thumb that provides articulation of the drive mechanism that causes rotation of a linear drive shaft encased in a barrel, which in turn causes a suturing needle encased in a disposable cartridge mounted at the distal end of the barrel to rotate in an advancing motion through the tissue. The device is, however, limited in its efficient operability in the following ways: (1) the rotational direction of the needle and the drive shaft is in a direction that is perpendicular to the device actuating handles, thereby rendering the device relatively difficult to manipulate and control, (2) does not allow the user to view the needle and its progress through the tissue during the suturing operation, since the barrel containing the drive shaft leading to the needle cartridge does not have an open construction to permit such observation, because the action of the needle is blocked from user's view by the nature of the instrument design, thereby making it difficult for the user to position the advancing needle with high accuracy along the junction of the incised tissue segments and (3) the rate of needle advancement and, therefore, the size and uniformity of the stitches is essentially controlled by the user by the extent to which the articulation mechanism is depressed, thereby rendering the process of obtaining uniform needle rotation, tissue penetration and suture advancement difficult and entirely dependent on the skill of the user.